1. Field of the Invention
The invention relates to magnetic particles, and in particular to magnetic particles with specific targeting functions for biomaterial separation and fabrication method thereof.
2. Description of the Related Art
Many biological materials such as nucleic acids present special challenges in terms of isolation from natural environments, often being present in very small concentrations and frequently found in the presence of many other solid and dissolved substances.
Accordingly, many procedures and materials for isolation of biological materials have been proposed, such as use of magnetic particles to adsorb biological materials, in which biological materials are agglutinated along with the magnetic particles. The agglutinate is separated from the original solvent by application of a magnetic field and a washing step.
Among several types of magnetic particle for isolating biological materials, an example is U.S. Pat. No. 6,133,047, which discloses superparamagnetic monodispersed particles comprising a core of a first polymer, an internal layer of a second polymer coating the core and in which a magnetic material is distributed, and an external layer of a third polymer coating the magnetic layer and capable of interacting with at least one biological molecule. U.S. Pat. No. 6,274,387 discloses a magnetic carrier comprising particulate silica containing a magnetic material, having polyacrylamide on the surface thereof. The surface of particulate silica containing the magnetic material is treated with a coupling agent, and the treated particulate silica is reacted with acrylamide and/or polyacrylamide. However, the properties of the magnetic particles are not sufficiently controllable.
There remains a need for a magnetic particle with controllable size, uniform diameter distribution, improved storage stability, and modified surface for specific targeting functions.